FREMONT — A fire destroyed a one-story bungalow in the Mission Valley neighborhood Wednesday afternoon and killed three German shepherd dogs.

There were no other deaths or injuries.

Firefighters arrived at the house about 2:05 p.m. at 1235 Austin St. and brought the blaze under control within 20 minutes, Battalion Chief Tom Mulvihill said.

Seventeen firefighters and two battalion chiefs responded to the blaze, which caused an estimated $500,000 in structural damage and $100,000 in contents damage, Mulvihill said.

The fire started after the homeowner cleaned out some fireplace ashes and placed them in a plastic container at the rear of the house, Mulvihill said. After a few hours, the container ignited and set fire to nearby combustible material.

By the time firefighters arrived, the back patio was fully engulfed in flames, which had broken through to the inside and spread to the kitchen, Capt. Jeff Youngsma said.

The homeowner, Frank Freitas, told a fire investigator that he was less than a block away at a family member’s house when he heard the sirens and returned.

He was too late, however, to rescue his dogs.

“All three of them,” said Freitas, looking dazed as black smoke billowed from the house and neighbors sought to keep him from bolting to his front lawn, where firefighters tried to resuscitate two of the dogs.

A third had died by the time rescuers brought it out.

A neighbor, Durga Toppur, said she called 9-1-1 when she saw plumes of gray smoke coming from Freitas’ house.

An unidentified man in a blue cap and sweat shirt tried to rescue the dogs, but the fire was too intense, Toppur said.

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